Climate Update 71 - May 2005

Backgrounder
Hail occurrence in New Zealand

Mean annual days of reported hailstorms taken from records for about 450 climate stations across New Zealand. Note that methods of observation, and the duration of reporting periods, are not consistent throughout the country.

Hailstorms are an inherent risk to primary production and other vulnerable activities throughout New Zealand. Hail records are available in New Zealand from climatological records, hourly weather reports at a few locations, and from the news media.

Climate Update is a summary each month of New Zealand’s climate, including soil moisture and river flows.
May 2005 – Number 71
April’s climate: April exceptionally dry and sunny. Frequent clear nights and a late southerly outbreak brought below average temperatures.
April’s river flows: Stream flows were low, especially in the north of the North Island.
Soil moisture levels: Low soil moisture in Northland.
Three-month outlook: Above average air temperatures in all districts.

The outlook for May 2005 to July 2005
Below average sea-level pressures are expected to the south of New Zealand, with enhanced westerly or northwesterly air flows over the country. Sea surface temperatures around New Zealand are likely to be near or above average to the end of July.
Air temperatures are expected to be above average in all districts.

Low soil moisture in Northland
Soil moisture deficits increased in much of Northland during April. At the end of the month, moisture levels were lower than normal also in parts of western Bay of Plenty, Manawatu, Nelson, central Marlborough, and the Mackenzie District. Moisture levels were higher than normal in Hawke’s Bay, Wairarapa, and Southland.
 
Soil moisture deficit in the pasture root zone at the end of April (right) compared with the deficit at the same time last year (centre) and the long-term end of April average (left).